eLabFTW is an electronic laboratory notebook system. Once installed on a server, every member of a lab can write up their experiments, upload files, manage a database of products (antibodies, chemicals, siRNA, papers, or whatever you want). It was created with usability and security in mind, is very easy to use, and has a long list of features specific to research life.

aFileDialog is an Android 2.2+ library that implements a simple and easy to use file chooser. The file chooser can be opened as a Dialog or as an Activity. You can filter files using regular expressions, select files or folders, and create files and folders.

exceptions4c is a tiny, portable framework that brings the power of exceptions to your C applications. It provides a simple set of keywords (macros, actually) which map the semantics of exception handling you're probably already used to: try, catch, finally, throw. You can write try/catch/finally blocks just as if you were coding in Java. This way you will never have to deal again with boring error codes, or check return values every time you call a function.